INCLUDE+=-I$(STMLIB)/CMSIS/Include

INCLUDE+=-I$(STMLIB)/CMSIS/Device/ST/STM32L1xx/Include

INCLUDE+=-I$(STD_PERIPH)/inc

INCLUDE+=-I$(DISCOVERY)

INCLUDE+=-I$(STMLIB)/$(OLEDDRV)

INCLUDE+=-I$(STMLIB)/$(USBDRV)

# vpath is used so object files are written to the current directory instead

# of the same directory as their source files

vpath %.c $(DISCOVERY) $(STD_PERIPH)/src \

          $(STMLIB)/USB \

          $(STMLIB)/STM32_USB-FS_Device_Library/Class/hid/src \

          $(STMLIB)/STM32_USB-FS_Device_Library/Core/src

vpath %.s $(STARTUP)

ASRC=startup_stm32l1xx_mdp.s

# Project Source Files

SRC=main.c

SRC+=stm32l1xx_it.c

SRC+=system_stm32l1xx.c

SRC+=stm32l100c_discovery.c

SRC+=ssd1306.c

SRC+=eeprom_min.c

SRC+=stringhelpers.c

# Discovery Source Files

#SRC+=stm32f4_discovery_lis302dl.c

#SRC+=stm32f4_discovery.c

#SRC+=stm32f4_discovery_audio_codec.c

# Standard Peripheral Source Files

SRC+=stm32l1xx_syscfg.c

SRC+=misc.c

SRC+=stm32l1xx_adc.c

SRC+=stm32l1xx_dac.c

SRC+=stm32l1xx_dma.c

SRC+=stm32l1xx_exti.c

SRC+=stm32l1xx_flash.c

SRC+=stm32l1xx_gpio.c

SRC+=stm32l1xx_i2c.c

SRC+=stm32l1xx_rcc.c

SRC+=stm32l1xx_spi.c

SRC+=stm32l1xx_tim.c

# USB Source Files

SRC+=usb_core.c

SRC+=usb_init.c

#ifndef CONFIG_H

#define CONFIG_H

#define SSR_PERIOD 200

#define LED_POWER GPIOB,GPIO_Pin_9

#define LED_STAT  GPIOA,GPIO_Pin_15

#define MAX_CS GPIOB,GPIO_Pin_12

#define SW_BTN  GPIOB, GPIO_Pin_3

#define SSR_PIN GPIOC, GPIO_Pin_13

#ifndef EEPROM_MIN_H

#define EEPROM_MIN_H

#define EEPROM_BASE_ADDR    0x08080000    

#define EEPROM_BYTE_SIZE    0x0FFF  

void Minimal_EEPROM_Unlock(void);

void Minimal_EEPROM_Lock(void);

FLASH_Status Minimal_FLASH_GetStatus(void);

FLASH_Status Minimal_FLASH_WaitForLastOperation(uint32_t Timeout);

void Minimal_EEPROM_ProgramWord(uint32_t Address, uint32_t Data);

#endif

#include "main.h"

#include "stm32l100c_discovery.h"

#include "ssd1306.h"

#include "config.h"

#include "eeprom_min.h"

// USB includes

#include "hw_config.h"

#include "usb_lib.h"

#include "usb_desc.h"

#include "usb_pwr.h"

#include "stringhelpers.h"

// TODO: Grab buttonpresses with interrupts

// USB Supporting Vars

extern __IO uint8_t Receive_Buffer[64];

extern __IO  uint32_t Receive_length ;

extern __IO  uint32_t length ;

uint8_t Send_Buffer[64];

uint32_t packet_sent=1;

uint32_t packet_receive=1;

// Globalish setting vars

uint8_t boottobrew = 0;

uint16_t k_p = 1;

uint16_t k_i = 1;

uint16_t k_d = 1;

volatile uint32_t ticks = 0;

int16_t setpoint_brew = 0;

int16_t setpoint_steam = 0;

// State definition

enum state {

    STATE_IDLE = 0,

    STATE_SETP,

    STATE_SETI,

    STATE_SETD,

    STATE_SETWINDUP,

    STATE_SETBOOTTOBREW,

    STATE_PREHEAT_BREW,

    STATE_MAINTAIN_BREW,

    STATE_PREHEAT_STEAM,

    STATE_MAINTAIN_STEAM,

};

uint8_t state = STATE_IDLE;

static __IO uint32_t TimingDelay;

// Move to header file

void process();

void machine();

void restore_settings();

void save_settings();

void save_setpoints();

int main(void)

{

    // Init clocks

    SystemInit();

    // Init GPIO

    init_gpio();

    // Turn on power LED

    GPIO_SetBits(LED_POWER);

    // TODO: Awesome pwm of power LED (TIM4_CH4 or TIM11_CH1)

    // Configure 1ms SysTick (change if more temporal resolution needed) 

    RCC_ClocksTypeDef RCC_Clocks;

    RCC_GetClocksFreq(&RCC_Clocks);

    SysTick_Config(RCC_Clocks.HCLK_Frequency / 1000);

    // Init SPI busses

    init_spi();

    // Init OLED over SPI

    ssd1306_Init();

    ssd1306_clearscreen();

    // Check for problems on startup

        temp_pre = temp_pre >> 2; // Drop 2 lowest bits

        temp_frac = temp_pre & 0b11; // get fractional part

        temp_frac *= 25; // each bit is .25 a degree, up to fixed point

        temp_pre = temp_pre >> 2; // Drop 2 fractional bits 

        if(sign) {

            temp = -temp_pre;

        }

        else {

            temp = temp_pre;

        }

    }

    // Deassert CS

    delay(1);

    GPIO_SetBits(MAX_CS);

}

// PID implementation

int16_t last_pid_temp = 0;

uint8_t last_pid_temp_frac = 0;

int16_t i_state = 0;

int16_t update_pid(uint16_t k_p, uint16_t k_i, uint16_t k_d, int16_t temp, uint8_t temp_frac, int16_t setpoint) 

{

  // Calculate instantaneous error

  int16_t error = (int16_t)setpoint - (int16_t)temp; // TODO: Use fixed point fraction

  // Proportional component

  int16_t p_term = k_p * error;

  // Error accumulator (integrator)

  i_state += error;

  // to prevent the iTerm getting huge despite lots of 

  //  error, we use a "windup guard" 

  // (this happens when the machine is first turned on and

  // it cant help be cold despite its best efforts)

  // not necessary, but this makes windup guard values 

  // relative to the current iGain

  // Calculate integral term with windup guard 

  if (i_state > windup_guard_res) 

    i_state = windup_guard_res;

  else if (i_state < -windup_guard_res) 

    i_state = -windup_guard_res;

  int16_t i_term = k_i * i_state;

  // Calculate differential term (slope since last iteration)

  int16_t d_term = (k_d * (temp - last_pid_temp));

  // Save temperature for next iteration

  last_pid_temp = temp;

  last_pid_temp_frac = temp_frac;

  int16_t result = p_term + i_term - d_term;

  // Put out tenths of percent, 0-1000. 

  if(result > 1000)

    result = 1000;

  else if(result < -1000)

    result = -1000;

  // Return feedback

  return result;

}

uint32_t last_ssr_on = 0;

uint32_t last_led = 0;

int32_t setpoint = 0;

int16_t ssr_output = 0; // Duty cycle of ssr, 0 to SSR_PERIOD 

uint8_t pid_enabled = 0;

// Process things

void process()

{

    update_temp(); // Read MAX31855

    // TODO: Add calibration offset (linear)

    if(ticks - last_led > 400) 

    {

        GPIO_ToggleBits(LED_POWER);

        last_led = ticks;

    }

    // Every 200ms, set the SSR on unless output is 0

    if((ticks - last_ssr_on > SSR_PERIOD))

    {

        if(pid_enabled) 

        {

    itoa_fp(temp, temp_frac, tempstr);

    //ssd1306_DrawString("        ", 3, 40);

    ssd1306_DrawString(tempstr, 3, 40);

    ssd1306_DrawString("-> ", 3, 80);

    itoa(setpoint, tempstr);

    ssd1306_DrawString("    ", 3, 95);

    ssd1306_DrawString(tempstr, 3, 95);

}

uint8_t goto_mode = 2;

// State machine

uint8_t sw_btn_last = 0;

uint8_t sw_up_last = 0;

uint8_t sw_down_last = 0;

uint8_t sw_left_last = 0;

uint8_t sw_right_last = 0;

#define SW_BTN_PRESSED (sw_btn_last == 0 && sw_btn == 1) // rising edge on buttonpress

#define SW_UP_PRESSED (sw_up_last == 0 && sw_up == 1)

#define SW_DOWN_PRESSED (sw_down_last == 0 && sw_down == 1)

#define SW_LEFT_PRESSED (sw_left_last == 0 && sw_left == 1)

#define SW_RIGHT_PRESSED (sw_right_last == 0 && sw_right == 1)

void save_settings()

{

   Minimal_EEPROM_Unlock();

    // Try programming a word at an address divisible by 4

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_BOOTTOBREW, boottobrew);

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_WINDUP_GUARD, windup_guard);

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_K_P, k_p);

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_K_I, k_i);

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_K_D, k_d);

    Minimal_EEPROM_Lock();

}

void save_setpoints()

{

    Minimal_EEPROM_Unlock();

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_BREWTEMP, setpoint_brew);

    Minimal_EEPROM_ProgramWord(EEPROM_BASE_ADDR + EEPROM_ADDR_STEAMTEMP, setpoint_steam); 

    Minimal_EEPROM_Lock();

}

void restore_settings()

{

    Minimal_EEPROM_Unlock();

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

    boottobrew = (*(__IO uint32_t*)(EEPROM_BASE_ADDR + EEPROM_ADDR_BOOTTOBREW));

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

    windup_guard = (*(__IO uint32_t*)(EEPROM_BASE_ADDR + EEPROM_ADDR_WINDUP_GUARD));

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

    k_p = (*(__IO uint32_t*)(EEPROM_BASE_ADDR + EEPROM_ADDR_K_P));

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

    k_i = (*(__IO uint32_t*)(EEPROM_BASE_ADDR + EEPROM_ADDR_K_I));

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

    k_d = (*(__IO uint32_t*)(EEPROM_BASE_ADDR + EEPROM_ADDR_K_D));

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

    setpoint_brew = (*(__IO uint32_t*)(EEPROM_BASE_ADDR + EEPROM_ADDR_BREWTEMP));

    while(Minimal_FLASH_GetStatus()==FLASH_BUSY);

    setpoint_steam = (*(__IO uint32_t*)(EEPROM_BASE_ADDR + EEPROM_ADDR_STEAMTEMP));    

    Minimal_EEPROM_Lock();

}

void machine()

{

    uint8_t last_state = state;

    uint8_t sw_btn = !GPIO_ReadInputDataBit(SW_BTN);

    uint8_t sw_up = !GPIO_ReadInputDataBit(SW_UP);

    uint8_t sw_down = !GPIO_ReadInputDataBit(SW_DOWN);

    uint8_t sw_left = !GPIO_ReadInputDataBit(SW_LEFT);

    uint8_t sw_right = !GPIO_ReadInputDataBit(SW_RIGHT);

    switch(state)

    {

        // Idle state

        case STATE_IDLE:

        {

            // Write text to OLED

            // [ therm :: idle ]

            ssd1306_DrawString("therm :: idle ", 0, 40);

            pid_enabled = 0;

            ssd1306_drawlogo();

            switch(goto_mode) {

                case 2:

                {

                    ssd1306_DrawString("-> brew     ", 1, 40);

                } break;

                case 1:

                {

                    ssd1306_DrawString("-> setup    ", 1, 40);

                } break;

                case 0:

                {

                    ssd1306_DrawString("-> reset    ", 1, 40);

                } break;

            }

            // Button handler

            if(SW_BTN_PRESSED) {

                switch(goto_mode) {

                    case 2:

        // Something is terribly wrong

        default:

        {

            state = STATE_IDLE;

            pid_enabled = 0;

        } break;

    }

    if(last_state != state) {

        // Clear screen on state change

        goto_mode = 2;

        ssd1306_clearscreen();

    }

    // Last buttonpress

    sw_btn_last = sw_btn;

    sw_up_last = sw_up;

    sw_down_last = sw_down;

    sw_left_last = sw_left;

    sw_right_last = sw_right;

}

// Delay a number of systicks

void delay(__IO uint32_t nTime)

{

  TimingDelay = nTime;

  while(TimingDelay != 0);

}

// ISR-triggered decrement of delay and increment of tickcounter

void TimingDelay_Decrement(void)

{

  if (TimingDelay != 0x00)

  { 

    TimingDelay--;

  }

  ticks++;

}